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تسجيل مستخدم جديدEROSITA study of the 47~Tucanae globular cluste
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We present the results of the analysis of five observations of the globular clutser 47 Tucanae (47 Tuc) with eROSITA (extended Roentgen Survey with an Imaging Telescope Array) on board Spektrum-Roentgen-Gamma (Spektr-RG, SRG). The aim of the work is the study of the X-ray population in the field of one of the most massive globular clusters in our Milky Way. We focused on the classification of point-like sources in the field of 47 Tuc. The unresolved dense core of 47~Tuc (1.7 radius) and also the sources, which show extended emission are excluded in this study. We applied different methods of X-ray spectral and timing analysis together with multi wavelength studies for the classification of the X-rays sources in the field of 47 Tuc. We detected 888 point-like sources in the energy range of 0.2-5.0 keV. We identified 92 background AGNs and 26 foreground stars. One of the foreground stars is classified as a variable M~dwarf. We also classified 23 X-ray sources as members of 47 Tuc, including 13 symbiotic stars, 3 quiescent low mass X-ray binaries, one millisecond pulsar candidate, and one cataclysmic variable. There are also 4 X-ray sources, which can be either a cataclysmic variable or a contact binary. Moreover, we calculated the X-ray luminosity function of 47 Tuc X-ray sources within a radius of 18.8. It shows that the main population of X-ray sources in 47 Tuc has a luminosity <10$^{32}$erg s$^{-1}$ in the energy range of 0.5-2.0 keV. These sources can mainly be candidates for quiescent low mass X-ray binaries and different types of accreting white dwarfs, especially symbiotic stars.
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